By integrating your AdSense account with a new or existing Analytics account, youâ€™ll have access to in-depth reports about user activity on your site. In addition to the wealth of metrics already available in Analytics such as unique visitors and visitor language, you’ll now have access to granular reports that break down AdSense performance both by page and by referring site. Armed with this new data about user behavior, youâ€™ll be able to make more informed decisions on how to improve the user experience on your site and optimize your AdSense units to increase your revenue potential.

You can watch a video overview of the features on YouTube:

More Integration?
This is great news for users who are already using both Google products. Taking it a step further, you would imagine Google will then be looking at integration for other products….
They have already begun migrating FeedBurner with your Google Account.
What would happen if you eventually migrated all of FeedBurner to be a part of Google Analytics? This would give webmasters a complete view. Not only would you be able to see your website stats, but also your feed stats from one console – now that would be cool.